Optical components which utilize or change a polarization state of light are widely used in a variety of applications, including inter alia communication systems, image generation systems, image display systems, and sensor devices. In more detail, devices for converting a linearly polarized light into circularly or elliptically polarized light are being investigated. Conventionally, λ/4 plates may be used for converting linearly polarized light into circularly polarized light and vice versa.
It is desirable to develop an improved optical resonator which is capable of converting the polarization state of light, which may be miniaturized to a large degree and which may be mounted on a substrate or integrated on a chip.